/*
---------------------------------------------------------------------------------------
This source file is part of SWG:ANH (Star Wars Galaxies - A New Hope - Server Emulator)

For more information, visit http://www.swganh.com

Copyright (c) 2006 - 2010 The SWG:ANH Team
---------------------------------------------------------------------------------------
Use of this source code is governed by the GPL v3 license that can be found
in the COPYING file or at http://www.gnu.org/licenses/gpl-3.0.html

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
---------------------------------------------------------------------------------------
*/

#include "CompCryptor.h"
#include <zlib.h>


//======================================================================================================================
CompCryptor::CompCryptor(void)
{
    mStreamData = new z_stream;
}


//======================================================================================================================
CompCryptor::~CompCryptor(void)
{
    delete mStreamData;
}

//======================================================================================================================
int CompCryptor::Compress(int8* inData, uint32 inLen, int8* outData, uint32 outLen)
{
    // Init our stream
    mStreamData->zalloc = Z_NULL;
    mStreamData->zfree = Z_NULL;
    mStreamData->opaque = Z_NULL;
    mStreamData->avail_in = 0;
    mStreamData->next_in = Z_NULL;
    deflateInit(mStreamData, Z_DEFAULT_COMPRESSION);

    // Setup our struct
    mStreamData->next_in = (Bytef*)inData;
    mStreamData->avail_in = inLen;
    mStreamData->next_out = (Bytef*)outData;
    mStreamData->avail_out = outLen;

    // compress our data and get it's final size.
    deflate(mStreamData, Z_FINISH);
    uint32 outBytes = mStreamData->total_out;
    if (outBytes)
    {
        // We only call this on a successful decompression.
        deflateEnd(mStreamData);
    }

    // May as well not compress it if it's going to be bigger.
    if (outBytes > inLen)
    {
        return 0;
    }

    return outBytes;
}


//======================================================================================================================
int CompCryptor::Decompress(int8* inData, uint32 inLen, int8* outData, uint32 outLen)
{
    // If it's not compressed, don't decompress it.
    if (inData[0] != 'x')
        return 0;

    // Init our stream
    mStreamData->zalloc = Z_NULL;
    mStreamData->zfree = Z_NULL;
    mStreamData->opaque = Z_NULL;
    mStreamData->avail_in = 0;
    mStreamData->next_in = Z_NULL;
    inflateInit(mStreamData);

    // Setup our struct
    mStreamData->next_in = (Bytef*)inData;
    mStreamData->avail_in = inLen;
    mStreamData->next_out = (Bytef*)outData;
    mStreamData->avail_out = outLen;

    // compress our data and get it's final size.
    inflate(mStreamData, Z_FINISH);
    uint32 outBytes = mStreamData->total_out;
    if (outBytes)
    {
        // We only call this on a successful decompression.
        inflateEnd(mStreamData);
    }

    return outBytes;
}


//======================================================================================================================
int CompCryptor::Encrypt(int8* data, uint32 len, uint32 seed)
{
    //seed = seed ^ 0x62491908;

    int retVal = 0;

    //uint32 tempSeed = 0;
    uint32 blockCount = (len / 4);
    uint32 byteCount = (len % 4);

    for(uint32 count = 0; count < blockCount; count++)
    {
        ((uint32*)data)[count] ^= seed;
        seed = ((uint32*)data)[count];
    }

    for(uint32 count = blockCount * 4; count < blockCount * 4 + byteCount; count++)
    {
        data[count] ^= seed;
    }

    return retVal;
}


//======================================================================================================================
int CompCryptor::Decrypt(int8* data, uint32 len, uint32 seed)
{
    //seed = seed ^ 0x62491908;

    int retVal = 0;

    uint32 tempSeed = 0;
    uint32 blockCount = (len / 4);
    uint32 byteCount = (len % 4);

    for(uint32 count = 0; count < blockCount; count++)
    {
        tempSeed = ((uint32*)data)[count];
        ((uint32*)data)[count] ^= seed;
        seed = tempSeed;
    }

    for(uint32 count = blockCount * 4; count < blockCount * 4 + byteCount; count++)
    {
        data[count] ^= seed;
    }

    return retVal;
}


//======================================================================================================================
uint32 CompCryptor::GenerateCRC(int8* data, uint32 len, uint32 seed)
{
    uint32 newCRC = 0, index = 0;

    newCRC = mCrcTable[(~seed) & 0xFF];
    newCRC ^= 0x00FFFFFF;
    index = (seed >> 8) ^ newCRC;
    newCRC = (newCRC >> 8) & 0x00FFFFFF;
    newCRC ^= mCrcTable[index & 0xFF];
    index = (seed >> 16) ^ newCRC;
    newCRC = (newCRC >> 8) & 0x00FFFFFF;
    newCRC ^= mCrcTable[index & 0xFF];
    index = (seed >> 24) ^ newCRC;
    newCRC = (newCRC >> 8) &0x00FFFFFF;
    newCRC ^= mCrcTable[index & 0xFF];

    for(uint32 i = 0; i < len; i++ )
    {
        index = (data[i]) ^ newCRC;
        newCRC = (newCRC >> 8) & 0x00FFFFFF;
        newCRC ^= mCrcTable[index & 0xFF];
    }

    return ~newCRC;
}


//======================================================================================================================
const uint32 CompCryptor::mCrcTable[256] =
{
    0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
    0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
    0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
    0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
    0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
    0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
    0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
    0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
    0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
    0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
    0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
    0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
    0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
    0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
    0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
    0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
    0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
    0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
    0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
    0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
    0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
    0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
    0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
    0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
    0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
    0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
    0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
    0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
    0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
    0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
    0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
    0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
    0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
    0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
    0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
    0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
    0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
    0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
    0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
    0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
    0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
    0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
    0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

